(FORTUNE Magazine) – The Big Test: The Secret History of the American Meritocracy by Nicholas Lemann Farrar Straus & Giroux, 406 pages

Remember getting your SAT scores in high school? I do. To my horror, my boyfriend's mother proudly announced my results, both verbal and math, to the guests at her annual Christmas party. "With those great scores, you're set for life," a party guest told me afterward, thumping me on the back. I walked away, mortified. How did one stupid test get to be such a big deal, such a wrenching adolescent rite of passage?

For the answer to that question, read Nicholas Lemann's fascinating and thoughtful new book, The Big Test: The Secret History of the American Meritocracy. It documents how the SAT has changed our lives and our country. Based on a bunch of little circles we filled in with a No. 2 pencil when we were 16, the SAT has assigned each of us a number value that sticks for life. And those number values, Lemann says, have created a new ruling class in America, pushing aside the old cadre of languid WASPs who dominated the top schools before World War II and replacing them with a collection of brainy snots of random pedigree who have gained access to money and privilege--all based on one little score. This is a sweeping book by a prominent journalist who has explored the American Dream and where it falls short in The Washington Monthly, the Atlantic Monthly, and in his earlier book, The Promised Land: The Great Black Migration and How It Changed America. His new book is written with his usual grace and is told movingly through the lives of the people involved; The Big Test makes you look at your world, your successes, and your high school boyfriend's mother a bit differently.

Lemann devotes the first third of the book to the tragicomic history of the SAT and how it shook up the old elite. The test as we know it got its start when the president of Harvard, James Bryant Conant, grew disgusted with the lazy bluebloods populating his campus in the 1930s. Weren't there smarter, more eager kids out there? Conant believed in what Thomas Jefferson described as a "natural aristocracy" of superior people "raked from the rubbish." How could Conant rake up some of that talent for Harvard, people who could then go on to lead the country more competently than the traditional aristocracy of well-born men? Well, it so happens that when Conant was asking those questions, America was developing its first IQ tests, and there was great enthusiasm about their ability to order and categorize people rationally. Conant fell upon the idea with missionary zeal. The IQ test, which evolved into the SAT, would be an instrument that reordered American life.

But what a strange instrument. Lemann illustrates the absurdity of this test as a way to measure people with sample questions from the first SAT:

Say which word, or both or neither, has the same meaning as the first word:

impregnable terile vacuous nominal exorbitant didactic

(The book doesn't supply the answer. I'm guessing neither, since terile [unless it's a typo] is not in the Oxford English Dictionary. Was terile made up to confuse test takers?) Lemann writes, "Someone who had never heard of such tests and was given one out of the blue might find incredible the proposition that three hours of this kind of questioning could bring to light the dimensions of the mind, and that a total of answers gotten right and wrong could be used to decide what place in society a person should occupy."

But as The Big Test demonstrates, that's just what happened. The SAT and the institution that's behind it, the Educational Testing Service, grew powerful enough to start changing the makeup of college campuses, to the dismay of old-school alums who worried that their alma maters were filling

up with nerds from God knows where instead of their own sons. William F. Buckley Jr., Yale '50, complained in 1968, "The son of an alumnus, who goes to a private preparatory school, now has less chance of getting in than some boy from P.S. 109 somewhere." So profound was this transformation that it reached to the highest levels of power in America. Lemann writes, "The effect of the change was neatly demonstrated a generation later, in 1993, when the White House was turned over from George and Barbara Bush, he Old Yale, from Greenwich, Conn., a Skull and Bones man, she a college dropout who had met him at a debutante ball, to Bill and Hillary Clinton, who, having been plucked out of public high school obscurity in the South and Midwest, had met in the library of Yale Law School in the late 1960s."

Lemann's description of this transformation--the rise of the SAT and the fall of the WASP--in the first part of the book is eye-opening stuff. But he runs into trouble when he gets past the history and into the implications. The breadth of his reporting is wonderful, but he sometimes stretches too far when he tries to explain a vast swath of post-war U.S. social history--the development of the public university system in California, the debate over affirmative action in college admissions, and the rise of Ronald Reagan--through the SAT lens. He's marshaled this information to drive home his central point: Using tests and the educational system to choose a few lucky kids to join the meritocracy is not compatible with our American ideals of democracy. There's nothing wrong with choosing the best person for the best job, he says. But using a single test to anoint a meritocracy that will lead America is wrong. (And if you think the new meritocrats are nobler than the WASPs they've replaced, just look at the Clintons.) So, Lemann recommends, let's stop using the SAT in college admissions. Instead, his solution is to make high-quality high school education available to all kids, and to that end develop a national curriculum and test their mastery of it to decide who gets into college.

But what if a kid gets a string of lousy history teachers? And would Americans, wedded as we are to local control over education, ever accept a national curriculum? Not likely. But even if his recommendations can never work, Nicholas Lemann--a private-school kid who went to Harvard--has written a book that sheds light on some of our stickiest dilemmas. Read it; it'll get you thinking.

--Erin Kelly

ERIN KELLY is an editor at FORTUNE;